1. Field of the Invention
The present invention relates to Traumatic Brain Injury (TBI including mild Traumatic Brain Injury or mTBI) and psychological health, and more specifically to quantitative, noninvasive, clinical diagnosis of traumatic brain injury, particularly for military applications. The present invention is directed to noninvasive rapid screening of mild traumatic brain injury using combination of subject's objective oculomotor, vestibular and reaction time analytic variables.
2. Background Information
Traumatic Brain Injury (TBI) is the result of a blunt blow, jolt or blast overpressure to the head that disrupts brain function. The subset of mild TBI, or mTBI, has represented a harder segment of TBI to diagnose. Within this application mTBI is a subset of TBI. The terms mild TBI (mTBI) and concussion are commonly used interchangeably in the art, and have been linked with Post Traumatic Stress Disorder. The severity of head injuries range from a brief change in mental status or consciousness to extended unconsciousness and amnesia. In severe or multiple concussion cases, personality changes can occur with devastating results.
Military personnel, despite using strong protective devices, frequently suffer blast injuries to the head. In a study conducted at the Walter Reed Army Medical Center, 62% of Operation Iraqi Freedom combat wounded troops showed symptoms of mild to severe brain injuries and of these, 91.6% had possibly sustained a TBI injury as a result of a blast. A number of recent studies have substantiated the presence of vestibular deficits in the acute period following TBI. The Defense and Veterans Brain Injury Center (www.dvbic.org) is a part of the U.S. Military Health System, specifically, it is the traumatic brain injury (TBI) operational component of the Defense Centers of Excellence for Psychological Health and Traumatic Brain Injury (DCoE) founded in 1992 by Congress, and represent a source for further detailed background and state of the art for TBI and the effect on the military.
Proper treatment of TBI injury requires an accurate diagnosis of the structures affected. Proper treatment of TBI injury requires an accurate diagnosis of the structures affected. The mechanisms of injury in TBI cause a variety of abnormalities in the peripheral vestibular mechanisms, central vestibular structures, ocular-motor tracts, cerebellum, as well as all portions of the brain communicating with these structures. The onset of vestibular deficits generally occurs within seven to ten days post injury. While reported symptoms of dizziness resolve after three months, 15% have persistent symptoms one year later.
Existing screening and diagnostic tools employed on patients with balance and neurological disorders associated with TBI based on the traditional battery of vestibular, balance and neurological tests requires the use of large stationary systems (neuro-otologic test center, Barany/rotary chair, ENG/VNG, computerized posturography/balance platforms, etc.). These large systems deploy a full battery of ocular motor, motion, artificial motion, balance and combined tests. Utilizing such devices may be practical in hospital settings, but are not useful in forward deployed military settings, or remote locations, such as first responder emergency medical technicians (EMTs).
The Centers for Disease Control and Prevention estimates that at least 3.17 million Americans currently have a long-term or lifelong need for help to perform activities of daily living as a result of a TBI. Currently there is no accepted clinical method to objectively detect mTBI. The Center for Disease Control (at http://www.cdc.gov/TraumaticBrainlnjury/statistics.html) estimates that “About 75% of TBIs that occur each year are concussions or other forms of mild TBI.” For further background please see Brain Injury Association of America at www.BIAUSA.org as The Brain injury Association of America (BAN) is the country's oldest and largest nationwide, brain injury advocacy organization.
For background on TBI assessment systems see U.S. Pat. No. 8,568,311 developed by Emory University which discloses an immersive cognitive assessment system which suppresses outside video and audio inputs. The '311 patent, which is incorporated herein by reference, discloses a distinct approach to the TBI assessment and is helpful to further establish the state of the art, including a relatively comprehensive listing of publications in the field.
It is the object of the present invention to address the deficiencies of the prior art.